A general cellular network configures a radio communication link having high mutual reliability through a centralized cell design in which communication is performed through a direct link between a base station and a terminal in a cell covered by the base station.
However, recently, communication networks tend to use a high service frequency band, and the radius of cells tends to be reduced in order to support high speed communication and accommodate a larger amount of calls, so the use of the existing centralized cellular radio network scheme as it is in the future involves many problems. Namely, since the location of a base station is fixed, flexibility of a radio link configuration deteriorates, having a difficulty in providing an effective communication service in a radio environment in which a traffic distribution or a call request amount are excessively changed.
Thus, a next-generation communication system should be distributedly controlled and established and actively cope with a change in an environment such as an additional installation of a new base station, and as a solution to the foregoing problems, a relay system has been proposed. A relay system is advantageous in that it extends cell service coverage by covering a partial shadow area generated in a cell region and increases a system capacity. In addition, a relay (referred to as a ‘relay station’, hereinafter) may be used at an initial situation when service requests are relatively low to reduce the burden of an initial installation cost.
In a system using a relay station, a user to which resource is directly allocated through a base station and a user to which resource is allocated by way of the relay station coexist. In this case, the base station is supposed to perform scheduling in consideration of all of the amount of packets served by the base station, the amount of packets served by the relay station, the size of a queue of the base station, and the size of a queue of the relay station, to thus optimize a packet transfer rate and equally allocate resources to all the users. However, currently, a scheduling method in consideration of the foregoing matters has yet to be proposed for such a relay system.